A second person is facing criminal charges months after a Texas mother allegedly left her two toddler children in a hot car for more than 15 hours.

The San Antonio Express-News reported that Amanda Hawkins was indicted in August on two charges of injury to a child and two charges of endangering for the deaths of her daughters, Brynn Hawkins, 1, and Addyson Overgard-Eddy, 2.

On Friday, a Kerr County judge determined that a second suspect, Kevin Franke, 17, can be tried as an adult if indicted on two charges of manslaughter, two charges of injury to a child, and two charges of child abandonment.

“We chose to seek certification based on the egregious nature of the crime, the man’s conduct following the deaths of the two small children, and the inability to properly serve and rehabilitate him in the juvenile system due to his age,” Kerr County Attorney Heather Stebbins said of Franke, who was 16 at the time of the incident.

As CrimeOnline previously reported, Hawkins, then 19, allegedly left her crying daughters in the car on June 6 while she partied at a 16-year-old male friend’s house. Police say the girls were left in the vehicle overnight and into the morning–when temperatures reached 92 degrees.

Sheriff Rusty Hierholzer claimed that several partygoers suggested that Hawkins bring her children inside but she declined.

“They’ll cry themselves to sleep,” the mother said, according to Hierholzer.

Though Stebbins declined to provide details about their case against Franke, defense attorney Joe Gonzales said that Franke slept in Hawkins’ SUV during the early hours of June 7 because there wasn’t enough space in the home. Gonzales maintained, however, that he wasn’t aware that the girls were sleeping in the back seat, the local paper reported.

Gonzales went on to note that Franke was the person who urged Hawkins to get medical care for the toddlers after they were found unresponsive.

“This is not the type of case that rises to the level of exposing a young man of his age to the adult judicial system,” the defense attorney said.

Stebbins said Monday that she intends to file misdemeanor charges against five other adults allegedly involved with the toddlers’ deaths.

Franke is being held on $310,000 bail, according to the Express-News. Meanwhile, Hawkins’ trial is scheduled to begin on March 26.